Fig. 5

a Radiograph during follow-up on 3 July 2017. This image shows that there is a cyst in the tooth root. b Radiograph of root canal treatment 22 August 2018. Root canal treatment was initiated; the root canal was thoroughly cleaned and disinfected, then filled with medication and covered; it was closely monitored during follow-up. c Radiographs after treatment on 9 March 2019. The root cyst in the affected area improved, and the patient’s pain disappeared